Arrangement for captive screw

ABSTRACT

A captive screw arrangement including a sleeve through which is extended a screw blank, after which the portion of the shank projecting beyond the sleeve is provided with screw threads of larger major diameter than the bore of the sleeve. A second bore of larger diameter is included, resulting in a thin-walled portion enabling a flange to be bent outwardly for attaching the sleeve to a workpiece. The interior of the sleeve beyond the first bore may be of sufficient length to allow retraction of the screw shank, and a third bore also may be provided to give the intermediate portion of the sleeve a thicker wall and greater strength than that at the thin-walled end.

United States Patent [72] Inventor Bulent Gulistan Malibu, Calif. [21]Appl. No. 777,992 [22] Filed Nov. 8, 1968 [45] Patented Mar. 23, 1971[73] Assignee Deutsch Fastener Corp.

Los Angeles, Calif. Continuation-impart of application Ser. No. 599,601,Oct. 3 1 1966, now abandoned.

- [54] ARRANGEMENT FOR CAPTIVE SCREW I 7 Claims, 8 Drawing Figs.

[52] U.S. Cl. 29/443,

29/512, 10/10, 10/155, 151/69 [51] lnt.C| ..B23pll/0t l, B23p 19/08,B21d 39/00, B2lh 3/02 [50] Field of Search 10/10, 86 (CL), 155.5;29/512, 522, 148.2, 443; 85/5; 151/69 [56] References Cited UNITEDSTATES PATENTS 1,251,676 1/1918 McCaffray 151/69 1,883,906 10/ 193 2Hasselquist l0 8 6 1O |6 Primary ExaminerRichard .l. Herbst AssistantExaminer-EM. Combs Attorney-Gausewitz & Carr ABSTRACT: A captive screwarrangement including a sleeve through which is extended a screw blank,after which the portion of the shank projecting beyond the sleeve isprovided with screw threads of larger major diameter than the bore ofthe sleeve. A second bore of larger diameter is included, resulting in athin-walled portion enabling a flange to be bent outwardly for attachingthe sleeve to a workpiece. The interior of the sleeve beyond the firstbore may be of sufficient length to allow retraction of the screw shank,and a third bore also may be provided to give the intermediate portionof the sleeve a thicker wall and greater strength than that at thethin-walled end.

PATENTED m2 3 l97l SHEET 1 UF 2 FIG. I

INVENTOR.

BULENT' GULISTAN ATTORNEYS FIG.5

PATENTEDNAR23|97| 3571.904.

' SHEET 2 OF 2 v A 50 M FIG. 8

INVENTOR.

BULENT GULISTAN F|G.7 BY

ATTORNEYS ARRANGEMENT FOR CAITIVE SCREW REFERENCE TO PARENT APPLICATIONThis is a continuation-in-part of my copending patent application Ser.No. 590, 601, filed Oct. 3 l, 1966, for Arrangement for Captive Screw,now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention This inventionpertains to a fastener of the type where a screw extends through areceptacle which is adapted for attachment to a workpiece.

2. The Prior Art Frequently, captive screw devices are complex itemsincluding involved arrangements that hold the'threaded screw to thereceptacle to prevent separation of these parts. As such, they areexpensive to manufacture, yet still often may permit the screw to becomeseparated from the receptacle. Other problems center around theattachment of the receptacle to the workpiece. This also may becomplicated and not fully reliable. Conventional captive screws maybecome loosened and separated from the workpiece under vibrational andother loads imposed upon them.

SUMMARY OF THE INVENTION According to this invention, a much simplercaptive screw is produced with a minimum of time and expense, yet thedevice is of superior performance capabilities. The present inventionincludes a receptacle in the form of a sleeve having a bore throughwhich the shank of the screw extends. The shank is threaded after it hasbeen passed through the bore, with threads being rolled on the outer endof the shank beyond the sleeve. These threads are rolled to a largeroutside diameter than the diameter of the opening through the sleeve, sothat the screw cannot move axially more than a limited distance due tothe interference between the threads and the sleeve. The head of thescrew, of course, prevents movement in the opposite direction. Thus, thescrew is permanently retained by the receptacle, which operation isaccomplished simultaneously with the forming of threads on the shank. Inthis manner, the threads are made to perform a dual function. The shankof the screw may initially have an enlarged distal end portion where thethreads are formed, with an inner part smaller in diameter than thesleeve bore to permit lateral floating of the screw.

Usually, the sleeve is fastened to the workpiece by means of flanges,one of which is preformed and the other of which is bent outwardly whenthe fastener is inserted through an opening in the workpiece,overlapping the surface of the workpiece to hold the sleeve in place.The sleeve, therefore, is retained by the workpiece while it cooperateswith the enlarged threaded portion of the screwto hold the screw to theworkpiece for limited axial movement relative thereto.

The bore in the sleeve may include a portion of larger diameter than thethreads to allow the threaded shank to be retracted into the sleeve. Theportion of larger diameter may be defined by a second bore that alsoresults in a thin-walled end to facilitate the bending of the flange.For greater strength, the sleeve may have a third and intermediate borethat will receive the threaded shank while providing a thicker wall thanat the end of the sleeve.

An object of this invention is to provide an improved simplified captivescrew.

Another object of this invention is to provide an arrangement for therapid and economical manufacture of captive screws.

A further object of this invention is to provide a captive screw inwhich the threads on the shank act both as the attaching means and asthe means for holding the screw against movement in one direction.

An additional object of this invention is to provide a captive screw inwhich the screw is permanently, securely and nonremovably retained bythe receptacle.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an exploded side elevationalview, partially in section, of the components of the fastener followingthe initial stage of manufacture;

FIG. 2 is a longitudinal sectional view of the fastener with the screwblank associated with the receptacle preparatory to the forming ofthreads on the shank of the screw;

FIG. 3 is a longitudinal sectional view of the completed fastenerattached to a workpiece;

FIG. 4 is a longitudinal sectional view, partially in elevation, of amodification of the fastener that provides for lateral float ingmovement of the screw and allows full retraction of the threaded end ofthe screw into the receptacle;

FIG. 5 is a longitudinal sectional view, partially in elevation, of amodified form of the invention in which the intermediate portion of thereceptacle wall is made stronger than in the design of FIG. 4, with thescrew blank being shown prior to forming the threads;

FIG. 6 is a view similar to FIG. 5, but with the threads produced on theend of the shank and withdrawn into the receptacle;

FIG. 7 is an end elevational view of the fastener; and

FIG. 8 is an end elevational view of the receptacle prior to receivingthe screw blank.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The fastener of this inventionis in two parts, one of which is the screw 10 and the other a tubularreceptacle Il. As illustrated in FIG. I, the screw 10 first is formed asa blank having a straight cylindrical shank I2 at one end of which is ahead I3 of any desired configuration. The receptacle II is constructedas a sleeve or collar which is shorter axially than the shank I2 of thescrew. The receptacle has an axial bore I4 extending inwardly from oneend, joining a remaining enlarged bore portion 115 that extends to theopposite end. At the end of the receptacle II adjacent the bore I4 is aradially outwardly projecting flange lb. The receptacle II for theremainder of its length exteriorly has a cylindrical surface I7 ofconstant diameter. Moreover, the wall of the receptacle is continuous,with no slots or openings interrupting its continuity.

After the two components of the fastener have been formed to thecondition of FIG. I, the shank I2 is inserted into the bores 14 and 15,as illustrated in FIG. 2. The bore I4 is dimensioned to receive theshank rather closely with a sliding fit, so that the screw member It)can be both rotated and moved axially relative to the receptacle II.There is a clearance between the wall of the shank I2 and the interiorsurface of the receptacle at the larger portion I5 of the bore. With theshank I2 being longer than the receptacle, it has an end portion 18projecting beyond the outer edge I9 of the receptacle II when the headI3 is positioned adjacent the flange I6.

After the screw II} has been extended through the receptacle II in themanner shown in FIG. 2, threads then are formed on the outer end portionT8 of the shank I2. This is accomplished by a rolling operation. A die20 of conventional design is moved laterally relative to the screw blankto bear against the end portion 18 of the shank 12. Then, upon relativerotation of the shank and die, threads 211 are formed on the end of thescrew I When the threads are rolled on the shank I2 in this manner, theyare caused to project outwardly beyond the surface of the shank l2,providing a greater overall diameter at the end portion IE.Consequently, the major diameter of the threads 23 is larger than thediameter of the shank i2 inwardly of the threads. This major diameteralso is greater than that of the bore 14 of the receptacle 11. As aresult, the threads 21 hold the screw to the receptacle 11. Once thethreads 21 have been rolled on the end portion 18, it becomes impossibleto move the screw axially in one direction (to the left as illustrated)more than a limited distance because the threads 21 cannot pass throughthe bore 14. Instead, the outwardly projecting threads will engage theshoulder 22 between the bores 14 and 15, which thereby stops the screw10 from movement in that direction. The threads and the shoulder 22,therefore, define an abutment arrangement that limits the movement ofthe screw relative to the receptacle. Of course, movement in theopposite direction is precluded by the screw head 13, which allowsmovement only to the point where its undersurface 23 engages the outerface of the flange 16.

Thus, by the simple process of rolling threads on the end of the shankof the screw member following its insertion into the bore of thereceptacle, a captive screw is provided. The threads are made to performa dual function, both holding the screw to the receptacle and providingthe means for engagement with the mating threaded opening. By a singleoperation, therefore, the screw member is completed and the retainingmeans is formed. The screw is held securely and with permanency to thereceptacle. There are no slots or gaps in the receptacle which wouldweaken its wall and raise the danger of its opening up to allowseparation of the screw from the receptacle. The screw and receptacleare held together such that it requires destruction of one or the otherin order to separate them. Nevertheless, the screw may move freelythrough its limited axial distance for engagement with the matingthreaded opening.

In use of the captive screw of this invention, the receptacle 11 isattached to a workpiece as indicated in FIG. 3. The workpiece 24 isprovided with an aperture 25 dimensioned to receive the cylindricalexterior surface 17 of the receptacle 11. Then the receptacle isinserted through the opening 25 in the workpiece 24, bringing the flange16 into engagement with the surface 26 of the workpiece adjacent one endof the opening 25. The receptacle 11 is longer than the thickness of theworkpiece 24 at the opening 25 so that the end of the receptacleprojects beyond the surface 27 of the workpiece. At this time, theprojecting end of the receptacle is bent outwardly, as shown in FIG. 3,to provide a radially extending flange 28 that overlaps the workpiecesurface 27 at the other end of the opening 25. The provision of theenlarged bore portion through the receptacle 11 results in a thinnerwall at that end of the receptacle, which facilitates the outwardbending to form the flange 28. The attachment of the receptacle to theworkpiece, therefore, is also a simple operation, so that, by merelybending a flange outwardly, the receptacle is securely held and retainedby the workpiece. The receptacle 11, in turn, cooperating with thethreads 21, secures the screw 10 to the workpiece so that it will beengageable with a mating threaded opening and will at all times be inposition on the workpiece when the fastener is loosened.

The fastener should be made, as illustrated, with an appreciable lengthto the bore 14 beyond (to the left of) the shoulder 22. This is toassure that the threads 21 cannot pass the shoulder 22 and allow thescrew 10 to escape the receptacle 11, even though an end force isimposed on the shank 12. Such a force may be applied when the screw isbeing loosened from a mating part, with a portion of the threadsengaging the threaded opening in the mating part, while the inner endthread bears against the shoulder 22. If the bore section 14 is short,the effect is only that of a thin flange where the shoulder 22 engagesthe inner end of the threads 21. The threads 21 then, in some instances,can distort the resulting thin flange and form mating internal threadsin it, so that the screw 10 may then be unthreaded completely from thereceptacle 11. However, with the bore 14 of appreciable length, thiscannot occur as the shoulder 22 becomes-relatively thick axially. It hasbeen found that a length of .060 inch is the minimum practical lengthfor the bore portion 14 in typical fasteners having aluminumreceptacles.

The embodiment of FIG. 4 is constructed to allow the screw to floatlaterally relative to the receptacle while still retaining the screwagainst movement out of the receptacle. This floating movement often isadvantageous where possible misalignment of the threaded opening in theadjacent part may occur. Also, in the arrangement of FIG. 4, the shankof the screw will retract entirely within the receptacle, so that aflush surface is provided. In certain instances it is desired to becertain that the shank of the fastener will not project beyond the endof the receptacle as this embodiment accomplishes.

The screw 29 of the design of FIG. 4 includes a slotted head 30 fromwhich projects an unthreaded shank portion 31. Outwardly of the shankportion 31 is a section 32 of greater 1 diameter than the part 31. Thethreads 33 are rolled on the outer portion 32 after the shank has beenextended through the receptacle 34. Thus, as before, with the end part32 projecting beyond the receptacle, the threads 33 are formed on theouter end of the shank.

The receptacle 34 includes a bore 35 adjacent the preformed end flange36. A counterbore 37 entering from the opposite end is of greaterdiameter than the bore 35. The device is constructed, therefore, suchthat the outer part of the shank with the threads 33 thereon is of adiameter such that it cannot pass through the bore 35 at the flange endof the receptacle 34. The threaded portion 33, however, can enter thelarger counterbore 37.

The length of the counterbore 37 is proportioned such that the endthreaded section of the shank can fit all the way in the receptacle.Therefore, when the device is installed and the attaching flange 38 isbent outwardly over the workpiece 39, the shank can be withdrawncompletely into the receptacle with none of the shank projecting beyondthe end of the receptacle. This retraction of the shank may befacilitated by providing a knurled periphery 40 on the head 30 of thescrew. In order to compensate for the longer counterbore 37 in thisversion of the invention so that the receptacle 34 will have adequatestrength, the flange 36 is made thicker than the flange 16 in thepreviously described embodiment.

The shank portion 31 of reduced diameter allows the screw to floatlaterally relative to the receptacle 34. The portion 31 is somewhatsmaller than the diameter of the bore 35, providing a clearance thatpermits this lateral movement to take place. At the same time, thelarger end section of the shank with its rolled threads 33 cannot passthrough the bore 35, so that the screw is held to the receptacle. Thisallows there to be the positive retention of the previously describedembodiment, while adding to the versatility of the fastener inpermitting it to engage misaligned threaded openings in the adjacentworkpiece.

The arrangement of FIGS. 5 through 8 also provides a retractable screwthat may be withdrawn entirely within the receptacle. This design isparticularly useful for longer fasteners in which the receptacle mustfit through thicker panels, providing for greater strength in thereceptacle than in the design of FIG. 4.

The receptacle 41 has a relatively small bore portion 42 adjacent theend where the flange or head 43 projects outwardly from the receptacle.In this instance, the flange 43 is frustoconical to provide for a flushinstallation, but otherwise is equivalent to the flanges 16 and 36described above. The receptacle 41 includes a second intermediate boreportion 44, providing a radial shoulder 45 between it and the smallerbore section 42. A third and still larger bore 46 results in athinwalled section 47 at the end of the tubular receptacle. The wall 48of the receptacle at the intermediate bore 44 is substantially thickerthan the wall 47 at the end.

The screw blank 49, in this instance illustrated with a flush head 50 tofit within a frustoconical recess 51 in the receptacle, is positioned inthe receptacle so that its unthreaded shank 52 extends through andbeyofid the end of the receptacle, as before. The shank is dimensionedso that it will slidably fit through the smaller bore section 42 while,of course, clearance is provided at the larger bore sections 44 and 46.

With the screw blank positioned as in FIG. 5, the threads 53 then arerolled on the end of the shank 52, providing it with a larger diameter.The parts are proportioned so that the threads 53 have a major diametersufficiently small to allow the threaded end to enter the intermediatebore section 4 4. However, the threads 53 have a larger major diameterthan that of the end bore 42, and are blocked by the shoulder 45 so thatthe screw cannot be withdrawn from the receptacle 4] after the threadshave been formed. Thus, the screw is retained by the receptacle.

The fastener assembly then is fitted into an opening 54 in a workpiece55, with the end of the thin-walled portion 47 projecting beyond thesurface of the workpiece adjacent the opening 54. The thin-walledsection 4'57 then is bent outwardly substantially at right angles toform a flange 56. This cooperates with the flange 43 on the receptaclein holding the receptacle to the workpiece. This, in turn, retains thescrew to the workpiece, with freedom for limited axial movement.

The bore section 44 is made sufficiently deep that the screw shank maybe withdrawn entirely into the receptacle 41 so that the screw does notthen project beyond the end of the receptacle, as shown in FIG. 6.However, unlike the version of HG. t, the provision of three boresections instead of two permits the. intermediate portion of thereceptacle to have a thicker wall 48 and, hence, to be stronger. This isimportant particularly where the receptacle is made relatively long tofit through a thicker panel. When the flange 56 is bent to attach thereceptacle to the workpiece, an inwardly directed force is applied tothe end of the receptacle 41, causing it to be loaded in compression. Ifthe thin-walled section 47 were to extend all the way to the shoulderd5, the receptacle would not in all instances possess adequateresistance to this compression load. Hence, it would become collapsedand distorted when the flange was formed. However, with'the provision ofthe intermediate bore 44 with a resulting thicker wall 48 for thereceptacle in its central portion, the receptacle possesses considerablygreater strength and can withstand the forces applied to it.

lclaim:

l. The method of providing a threaded fastener on a workpiece withfreedom for limited movement relative thereto comprising the steps of:

preparing a member having a head at one end and an integral elongatedsubstantially cylindrical shank projecting therefrom;

preparing a tubular member having:

an integral generally radially outwardly projecting flange at one endthereof;

a continuous circumferential wall extending to the opposite end of saidtubular member;

a first bore portion extending inwardly from said one end with saidfirst bore portion being dimensioned to slidably receive saidsubstantially cylindrical shank; and

a second bore portion larger than said first bore portion extendinginwardly from said opposite end of said tubular member so as to providea radially directed shoulder intermediate said bore portions and athin-walled portion of said tubular member adjacent said opposite end;

then extending said substantially cylindrical shank through said tubularmember to bring said head into adjacency with said flange and the distalend of said substantially cylindrical shank outwardly beyond saidopposite end of said tubular member;

then rolling threads on said distal end portion of said substantiallycylindrical shank to provide a major diameter less than said second boreportion but greater than said first bore portion so that said shoulderprevents removal of said shank from said member;

then extending said tubular member through an opening in I a workpiecethat is shorter at said opening than the length of said tubular memberand includes a surface radial with respect to said opening extendingtherefrom at one end of said opening so that at least a portion of saidthimwalled portion projects outwardly past said one end of said openingbeyond said surface of said workpiece and said flange is in engagementwith the surface of said workpiece at the opposite end of said opening;and

then bending said projecting portion of said thin-walled portionoutwardly through approximately so as to provide a second substantiallyradial flange on said tubular member overlapping said radial surface ofsaid workpiece beyond said one end of said opening in said workpiece forcooperation with said first-mentioned flange of said tubu lar member inholding said tubular member to said workpiece, whereby said tubularmember holds said shank with said threads thereon to said workpiece.

2. The method of providing a threaded fastener on a work piece withfreedom for limited movement relative thereto comprising the steps of:

preparing a member having a head at one end and an integral elongatedsubstantially cylindrical shank projecting therefrom;

preparing a tubular member of aluminum material having:

an integral outwardly projecting flange at one end thereof;

a continuous circumferential wall extending to the opposite end of saidtubular member;

a surface at said one end adapted for engagement by said head;

a bore portion of a predetermined diameter inwardly from said oppositeend thereof so as to provide a relatively thin bendable wall at saidopposite end; and

another bore portion of a relatively constant and smaller diametersubstantially complementary to said shank so as to be dimensioned toslidably receive said substantially cylindrical shank and extendinginwardly at least substantially .060 inch from said surface to said boreportion of predetermined diameter so as to provide an undeflectableshoulder between said bore portions;

then extending said substantially cylindrical shank through said boreportions to bring said head into adjacency with said surface and thedistal end of said substantially cylindrical shank outwardly beyond saidopposite end of said tubular member;

then rolling threads on said distal end portion of said substantiallycylindrical shank to provide a major diameter less than saidpredetermined diameter but greater than said smaller diameter so thatsaid shank prevents removal of said shank from said tubular member;

then extending said tubular member through an opening in a workpiecethat is shorter at said opening than the length of said tubular memberso that at least a portion of said thin-walled portion projectsoutwardly past said opening beyond the surface of said workpiece on oneside and said flange is adjacent the surface of said workpiece on theopposite side; and

then bending said projecting portion of said thin-walled portionoutwardly through approximately 90 so as to provide a secondsubstantially radial flange on said tubular member overlapping said oneside of said workpiece beyond said opening in said workpiece forcooperating with said first-mentioned flange of said tubular member inholding said tubular member to said workpiece,

whereby said tubular member holds said shank with said threads thereonto said workpiece.

3. The method of forming a captive screw comprising the steps of:

forming a first bore extending inwardly from one end of a sleeve memberadapted to be attached to a workpiece,

forming a second bore of larger diameter extending in wardly from theopposite end of said sleeve member and communicating with said firstbore so as to provide a shoulder therebetween;

providing an integral, abutment means on one end of an elongatedelement,

said abutment means being formed to a lateral dimension greater thanthat of said bore at one end of said sleeve member;

forming said elongated element to provide a portion of a first diametersmaller than said first bore adjacent said abutment means and a portionof a second and larger diameter at the opposite end thereof, with saidportion of said first diameter being longer than said first bore,extending said elongated element through said bores to bring saidabutment means into adjacency with said one end of said sleeve memberand to position said portion of second diameter of said elongatedelement so that it projects beyond said opposite end of said sleevemember, and to position said portion of first diameter of said elongatedelement in said first bore so that there is a clearance around saidelongated element at said first bore permitting limited lateral floatingmovement of said elongated element relative to said sleeve; and

then forming threads on said portion of second diameter of said elementso that said threads have a major diameter smaller than the diameter ofsaid second bore and greater than the diameter of said first bore sothat said portion of second diameter of said element is prevented bysaid shoulder from being moved back through said first bore and removedfrom said sleeve member,

said threads being formed to an axial length shorter than that of saidsecond bore so that said portion of second diameter of said element isretractable in its entirety into said sleeve member.

4. The method of providing a threaded fastener on a workpiece withfreedom for limited movement relative thereto comprising the steps of:

preparing a stud member having a head at one end and an integralelongated substantially cylindrical shank projecting therefrom;

preparing a tubular member having:

an integral outwardly projecting flange at one end thereof;

a continuous circumferential wall extending from said flange to theopposite end of said tubular member;

a first bore portion adjacent said one end with said first bore portionbeing dimensioned to slidably receive said substantially cylindricalshank;

a second bore portion larger than said first bore portion adjacent saidfirst bore portion so as to provide a shoulder intermediate said firstand second bore portions; and

a third bore portion larger than said second bore portion extendinginwardly from said opposite end of said tubular member so as to providea thin-walled portion of said tubular member adjacent said opposite end;

extending said substantially cylindrical shank through said tubularmember to bring said head into adjacency with said flange and toposition the distal end of said shank outwardly beyond said opposite endof said tubular member, then rolling threads on said distal end of saidsubstantially cylindrical shank to provide a major diameter less thansaid second and third bore portions but greater than said first boreportion so that said shoulder prevents removal of said shank from saidtubular member;

extending said tubular member through an opening in a workpiece whichopening is shorter than the length of said tubular member so as toposition said flange in adjacency with the surface of said workpiece atone end of said opening, and to position a portion of said thin-walledportion outwardly past said opening at the opposite end of said opening;and

then bending said projecting portion of said thin-walled portionoutwardly to provide a second flange on said tubular member overlappingsaid workpiece beyond said opening in said workpiece for cooperatingwith said first-mentioned flange of said tubular member in holding saidtubular member to said workpiece, whereby said tubular member holds saidshank with said threads thereon to said workpiece and said threadedportion is retractable into said second bore portion in said tubularmember.

5. The method as recited in claim 4 in which for bending said secondflange said thin-walled portion is bent outwardly substantially at rightangles to the axis of said tubular member.

6. The method as recited in claim 4 in which said bore por tions areproportioned in length such that said shoulder is located inwardly ofsaid opposite end of said opening a distance such that after said secondflange is so bent said distal end is substantially entirely receivablewithin said tubular member.

7. The method of retaining a screw on a workpiece with freedom forlimited axial movement of the screw relative to the workpiece comprisingthe steps of:

preparing a first member having an elongated unthreaded cylindricalshank and an integral outwardly projecting head at one end of saidshank;

providing a tubular member of continuous circumferential wall and alength less than that of said shank;

providing an integral outwardly projecting flange on one end of saidtubular member;

providing a cylindrical unthreaded bore through said tubular member; sothat said bore has a first portion of a first diameter adjacent said oneend; and a second portion of a second and larger diameter extendinginwardly from the opposite end of said tubular member to a locationintermediate the ends thereof; so as to provide an opposite end portionhaving a relatively thin bendable wall of substantially constantthickness; and to define a solid undeflectable shoulder intermediatesaid first bore and said second bore; then extending said shank throughsaid bore in said tubular member so as to bring said head of said firstmember into adjacency with said flange of said tubular member, and toprovide a distal end portion of said shank projecting axially outwardlybeyond said opposite end of said tubular member; then rolling threads onsaid distal end portion of said shank at a location remote from saidshoulder so as to provide threads having a greater major diameter thansaid first diameter of said bore so that said shoulder will interferewith said threads to prevent removal of said shank from said bore in onedirection while allowing limited axial movement of said shank relativeto said tubular member;

providing a workpiece with an opening therethrough shorter than thedistance between said flange of said tubular member and said oppositeend thereof and of smaller diameter than the diameter of said flange ofsaid tubular member;

providing a first surface at one end of said opening, and a secondsurface at the opposite end of said opening such that said secondsurface is substantially perpendicular to the longitudinal axis of saidopening;

then extending said tubular member into said opening so as to bring saidflange of said tubular member into engagement with said first surface ofsaid workpiece, and to cause a part of said opposite end portion of saidtubular member to project outwardly beyond said second surface of saidworkpiece, with said shoulder being inwardly of said second surface ofsaid workpiece; and

then bending said relatively thin wall of said part of said opposite endportion outwardly through substantially to overlap said second surfaceof said workpiece and cooperate with said flange of said tubular memberto hold said tubular member and thus said first member to saidworkpiece.

1. The method of providing a threaded fastener on a workpiece withfreedom for limited movement relative thereto comprising the steps of:preparing a member having a head at one end and an integral elongatedsubstantially cylindrical shank projecting therefrom; preparing atubular member having: an integral generally radially outwardlyprojecting flange at one end thereof; a continuous circumferential wallextending to the opposite end of said tubular member; a first boreportion extending inwardly from said one end with said first boreportion being dimensioned to slidably receive said substantiallycylindrical shank; and a second bore portion larger than said first boreportion extending inwardly from said opposite end of said tubular memberso as to provide a radially directed shoulder intermediate said boreportions and a thin-walled portion of said tubular member adjacent saidopposite end; then extending said substantially cylindrical shankthrough said tubular member to bring said head into adjacency with saidflange and the distal end of said substantially cylindrical shankoutwardly beyond said opposite end of said tubular member; then rollingthreads on said distal end portion of said substantially cylindricalshank to provide a major diameter less than said second bore portion butgreater than said first bore portion so that said shoulder preventsremoval of said shank from said member; then extending said tubularmember through an opening in a workpiece that is shorter at said openingthan the length of said tubular member and includes a surface radialwith respect to said opening extending therefrom at one end of saidopening so that at least a portion of said thin-walled portion projectsoutwardly past said one end of said opening beyond said surface of saidworkpiece and said flange is in engagement with the surface of saidworkpiece at the opposite end of said opening; and then bending saidprojecting portion of said thin-walled portion outwardly throughapproximately 90* so as to provide a second substantially radial flangeon said tubular member overlapping said radial surface of said workpiecebeyond said one end of said opening in said workpiece for cooperationwith said firstmentioned flange of said tubular member in holding saidtubular member to said workpiece, whereby said tubular member holds saidshank with said threads thereon to said workpiece.
 2. The method ofproviding a threaded fastener on a workpiece with freedom for limitedmovement relative thereto comprising the steps of: preparing a memberhaving a head at one end and an integral elongated substantiallycylindrical shank projecting therefrom; preparing a tubular member ofaluminum material having: an integral outwardly projecting flange at oneend thereof; a continuous circumferential wall extending to the oppositeend of said tubular member; a surface at said one end adapted forengagement by said head; a bore portion of a predetermined diameterinwardly from said opposite end thereof so as to provide a relativelythin bendable wall at said opposite end; and another bore portion of arelatively constant and smaller diameter substantially complementary tosaid shank so as to be dimensioned to slidably receive saidsubstantially cylindrical shank and extending inwardly at leastsubstantially .060 inch from said surface to said bore portion ofpredetermined diameter so as to provide an undeflectable shoulderbetween said bore portions; then extending said substantiallycylindrical shank through said bore portions to bring said head intoadjacency with said surface and the distal end of said substantiallycylindrical shank outwardly beyond said opposite end of said tubularmemBer; then rolling threads on said distal end portion of saidsubstantially cylindrical shank to provide a major diameter less thansaid predetermined diameter but greater than said smaller diameter sothat said shank prevents removal of said shank from said tubular member;then extending said tubular member through an opening in a workpiecethat is shorter at said opening than the length of said tubular memberso that at least a portion of said thin-walled portion projectsoutwardly past said opening beyond the surface of said workpiece on oneside and said flange is adjacent the surface of said workpiece on theopposite side; and then bending said projecting portion of saidthin-walled portion outwardly through approximately 90* so as to providea second substantially radial flange on said tubular member overlappingsaid one side of said workpiece beyond said opening in said workpiecefor cooperating with said first-mentioned flange of said tubular memberin holding said tubular member to said workpiece, whereby said tubularmember holds said shank with said threads thereon to said workpiece. 3.The method of forming a captive screw comprising the steps of: forming afirst bore extending inwardly from one end of a sleeve member adapted tobe attached to a workpiece, forming a second bore of larger diameterextending inwardly from the opposite end of said sleeve member andcommunicating with said first bore so as to provide a shouldertherebetween; providing an integral abutment means on one end of anelongated element, said abutment means being formed to a lateraldimension greater than that of said bore at one end of said sleevemember; forming said elongated element to provide a portion of a firstdiameter smaller than said first bore adjacent said abutment means and aportion of a second and larger diameter at the opposite end thereof,with said portion of said first diameter being longer than said firstbore, extending said elongated element through said bores to bring saidabutment means into adjacency with said one end of said sleeve memberand to position said portion of second diameter of said elongatedelement so that it projects beyond said opposite end of said sleevemember, and to position said portion of first diameter of said elongatedelement in said first bore so that there is a clearance around saidelongated element at said first bore permitting limited lateral floatingmovement of said elongated element relative to said sleeve; and thenforming threads on said portion of second diameter of said element sothat said threads have a major diameter smaller than the diameter ofsaid second bore and greater than the diameter of said first bore sothat said portion of second diameter of said element is prevented bysaid shoulder from being moved back through said first bore and removedfrom said sleeve member, said threads being formed to an axial lengthshorter than that of said second bore so that said portion of seconddiameter of said element is retractable in its entirety into said sleevemember.
 4. The method of providing a threaded fastener on a workpiecewith freedom for limited movement relative thereto comprising the stepsof: preparing a stud member having a head at one end and an integralelongated substantially cylindrical shank projecting therefrom;preparing a tubular member having: an integral outwardly projectingflange at one end thereof; a continuous circumferential wall extendingfrom said flange to the opposite end of said tubular member; a firstbore portion adjacent said one end with said first bore portion beingdimensioned to slidably receive said substantially cylindrical shank; asecond bore portion larger than said first bore portion adjacent saidfirst bore portion so as to provide a shoulder intermediate said firstand second bore portions; and a third bore portion larger than saidsecond bore portion extending inwardly from said opPosite end of saidtubular member so as to provide a thin-walled portion of said tubularmember adjacent said opposite end; extending said substantiallycylindrical shank through said tubular member to bring said head intoadjacency with said flange and to position the distal end of said shankoutwardly beyond said opposite end of said tubular member, then rollingthreads on said distal end of said substantially cylindrical shank toprovide a major diameter less than said second and third bore portionsbut greater than said first bore portion so that said shoulder preventsremoval of said shank from said tubular member; extending said tubularmember through an opening in a workpiece which opening is shorter thanthe length of said tubular member so as to position said flange inadjacency with the surface of said workpiece at one end of said opening,and to position a portion of said thin-walled portion outwardly pastsaid opening at the opposite end of said opening; and then bending saidprojecting portion of said thin-walled portion outwardly to provide asecond flange on said tubular member overlapping said workpiece beyondsaid opening in said workpiece for cooperating with said first-mentionedflange of said tubular member in holding said tubular member to saidworkpiece, whereby said tubular member holds said shank with saidthreads thereon to said workpiece and said threaded portion isretractable into said second bore portion in said tubular member.
 5. Themethod as recited in claim 4 in which for bending said second flangesaid thin-walled portion is bent outwardly substantially at right anglesto the axis of said tubular member.
 6. The method as recited in claim 4in which said bore portions are proportioned in length such that saidshoulder is located inwardly of said opposite end of said opening adistance such that after said second flange is so bent said distal endis substantially entirely receivable within said tubular member.
 7. Themethod of retaining a screw on a workpiece with freedom for limitedaxial movement of the screw relative to the workpiece comprising thesteps of: preparing a first member having an elongated unthreadedcylindrical shank and an integral outwardly projecting head at one endof said shank; providing a tubular member of continuous circumferentialwall and a length less than that of said shank; providing an integraloutwardly projecting flange on one end of said tubular member; providinga cylindrical unthreaded bore through said tubular member; so that saidbore has a first portion of a first diameter adjacent said one end; anda second portion of a second and larger diameter extending inwardly fromthe opposite end of said tubular member to a location intermediate theends thereof; so as to provide an opposite end portion having arelatively thin bendable wall of substantially constant thickness; andto define a solid undeflectable shoulder intermediate said first boreand said second bore; then extending said shank through said bore insaid tubular member so as to bring said head of said first member intoadjacency with said flange of said tubular member, and to provide adistal end portion of said shank projecting axially outwardly beyondsaid opposite end of said tubular member; then rolling threads on saiddistal end portion of said shank at a location remote from said shoulderso as to provide threads having a greater major diameter than said firstdiameter of said bore so that said shoulder will interfere with saidthreads to prevent removal of said shank from said bore in one directionwhile allowing limited axial movement of said shank relative to saidtubular member; providing a workpiece with an opening therethroughshorter than the distance between said flange of said tubular member andsaid opposite end thereof and of smaller diameter than the diameter ofsaid flange of said tubular member; providing a first surface at one endof saiD opening, and a second surface at the opposite end of saidopening such that said second surface is substantially perpendicular tothe longitudinal axis of said opening; then extending said tubularmember into said opening so as to bring said flange of said tubularmember into engagement with said first surface of said workpiece, and tocause a part of said opposite end portion of said tubular member toproject outwardly beyond said second surface of said workpiece, withsaid shoulder being inwardly of said second surface of said workpiece;and then bending said relatively thin wall of said part of said oppositeend portion outwardly through substantially 90* to overlap said secondsurface of said workpiece and cooperate with said flange of said tubularmember to hold said tubular member and thus said first member to saidworkpiece.